To date, speech recognition scores have not been used to predict hearing thresholds. Hearing thresholds are not highly correlated with scores on conventional measures of speech recognition and, as such, it is counterintuitive that scores on any measure of speech recognition could be used to predict hearing thresholds.
The degree of an individual's hearing loss generally is quantified in terms of the magnitude or level of a sound needed for him/her to detect it. The smallest intensity of a sound needed by a person to detect its presence is referred to as his/her threshold for that sound. In practice, hearing threshold is defined as the lowest intensity at which an individual responds to a sound on approximately half of the occasions on which it is presented. Typically, the sounds used to test an individual's hearing are pure tones presented at different frequencies (i.e., octave intervals from 0.25 kHz to 8 kHz). Standard audiometric evaluations include the determination of pure-tone thresholds. Providing clinicians with estimates of clients' hearing thresholds prior to the audiometric evaluation could enhance efficiency in clinical practice in the same way that ophthalmologists enhance efficiency by having a technician administer an eye test for refraction prior to the patient seeing the doctor.
In clinical practice, hearing thresholds are determined via a standard testing procedure administered by an audiologist using specialized equipment (a properly calibrated clinical audiometer) in a specialized environment (a sound-treated booth) and, as such, cannot be determined over the internet. Hearing thresholds indicate the severity and configuration of hearing loss and serve as the input for programming hearing aids. They also can be used to determine whether or not a personal sound amplification product (PSAP) would be an appropriate option for individual consumers. Currently, people wishing to purchase a PSAP often have no way of knowing if it would be appropriate for them, so having information concerning their hearing thresholds would empower consumers to make better health care decisions. In addition, individuals wishing to purchase a programmable hearing aid over the internet must see a hearing health care provider to obtain their hearing thresholds. This represents an additional cost to the consumer. Hearing aid sales, unlike the sale of PSAPs, are regulated by the Food and Drug Administration, as well as state authorities. As such, government regulations currently require consumers to visit a licensed hearing health care provider in order to obtain their hearing thresholds for the purpose of programming hearing aids. Therefore, in principle, enabling hearing thresholds to be determined using a self-administered test delivered over the internet has the potential to facilitate direct sales of PSAPs and hearing aids to consumers, significantly reducing cost and increasing accessibility for millions of individuals.
Hearing aids are beginning to be sold directly to consumers over the internet at deep discounts from the normal retail cost. By selling hearing aids at deeply discounted prices, distributors are likely to cut into revenue for audiologists working within the current business model in which they serve as middlemen for dispensing hearing aids to consumers. Similarly, PSAPs cost considerably less than hearing aids and also are available over the internet and at some pharmacies and other retailers. The sale of these devices also is likely to cut into revenue for audiologists. The problem with the current business model in hearing health care is that it is not sustainable because the middleman's mark-up and services more than double the consumer's cost. Therefore, it is likely that hearing aids and PSAPs will continue to be sold directly to consumers over the internet, and alternative means of obtaining hearing thresholds will be needed to maximize their sales and accessibility to members of the general public, especially to first-time users of amplification and individuals who are highly cost-conscious.